v3.25.3
Document and Entity Information
Oct. 21, 2025
Cover [Abstract]  
Amendment Flag false
Entity Central Index Key 0001599298
Document Type 8-K
Document Period End Date Oct. 21, 2025
Entity Registrant Name Summit Therapeutics Inc.
Entity Incorporation State Country Code DE
Entity File Number 001-36866
Entity Tax Identification Number 37-1979717
Entity Address, Address Line One 601 Brickell Key Drive
Entity Address, Address Line Two Suite 1000
Entity Address, City or Town Miami
Entity Address, State or Province FL
Entity Address, Postal Zip Code 33131
City Area Code (305)
Local Phone Number 203-2034
Written Communications false
Soliciting Material false
Pre Commencement Tender Offer false
Pre Commencement Issuer Tender Offer false
Security 12b Title Common stock, $0.01 par value per share
Trading Symbol SMMT
Security Exchange Name NASDAQ
Entity Emerging Growth Company false